Tables are a common way to represent information in an organized way. Tables include a grid of typically multiple rows and typically multiple columns. Each row corresponds to a certain item, whereas each column corresponds to a property. Thus, a table entry at the intersection of a particular column and row represents a property value of a property corresponding to the particular column, the property value of the item corresponding to the particular row.
Tables are also represented as data structures in a computing system, and often rendered as tables on the computer display. Conventional computer table design has focused on visual formatting, such as the changing of row colors in tables inserted into a work processing application. Other designs relate to the formatting that can occur across rows. For example, rows can be sorted by income or grouped by date. Email programs often further allow some sorting where emails can be grouped by sender. Likewise, file system user interfaces often group file system entries by date. Spreadsheets can sort rows by the values in certain columns.